On a night the Mets should have been celebrating Hairston becoming the 10th player in team history to hit for the cycle, they were instead left dumbfounded over the 11 runs the Rockies scored in the fifth inning, with help from four errors.

Hairston got the cycle, but his team was caught in a spin cycle in an 18-9 loss at Coors Field that snapped a three-game winning streak.

“It’s just one of those days where it is bittersweet,” Hairston said. “It would have been a lot nicer if we won the game, but we didn’t.”

IT’S LOOSE! Catcher Mike Nickeas reaches for the ball as Jonathan Herrera runs toward home plate during Colorado’s 11-run fifth inning in the Mets’ 18-9 loss to the Rockies last night. (AP)

IT’S LOOSE! Catcher Mike Nickeas reaches for the ball as Jonathan Herrera runs toward home plate during Colorado’s 11-run fifth inning in the Mets’ 18-9 loss to the Rockies last night. (
)

Chris Schwinden struggled in his first start replacing injured Mike Pelfrey in the rotation, but that represented just a fraction of the Mets’ misery, considering the bullpen allowed 12 runs over four innings and the team committed six errors — one short of the franchise record.

Hairston already had a single, homer and triple when he came to bat in the sixth against reliever Josh Roenicke and sent a shot to deep left-center that went for a double. It gave Hairston the first Mets cycle since Jose Reyes accomplished the feat on June 21, 2006 against the Reds.

“Scotty had a great day and it’s going to go unnoticed on a day like this,” manager Terry Collins said.

In an inning from hell, the Mets tied club records for runs allowed (11) and errors (four) and fell behind 13-6 in the fifth. It was an inning that included three-run homers by Carlos Gonzalez and Dexter Fowler, after Schwinden had been afforded a four-run cushion in the top of the frame.

The tone for the inning was set when Schwinden threw wide of first base on an Eric Young comebacker leading off. Marco Scutaro walked and Jonathan Herrera’s single scored a run before Gonzalez hit a three-run bomb to tie the game and end Schwinden’s night.

Manny Acosta allowed a three-run homer to Dexter Fowler later in the inning. The Rockies broke it open with three more runs in the fifth after Fowler’s blast.

“This wasn’t a good way to go out and show myself,” said Schwinden, who allowed seven hits and five earned runs over four-plus innings. “But hopefully I get another opportunity to do that.”

As the Mets try to survive Pelfrey’s likely loss for the season with a torn ulnar collateral ligament, Collins has little choice but to hand Schwinden the ball every fifth day and hope the rookie right-hander can at least give the team a chance.

None of the options behind Schwinden are particularly appealing for the Mets, starting with the idea of 41-year-old Miguel Batista or largely untested Jeremy Hefner joining the rotation. And the organization still does not view heralded prospects Matt Harvey and Jeurys Familia as major-league ready.

“[Schwinden] is going to get an extended look,” Collins said, adding that the rookie will start again on Wednesday in Houston. “We brought him here for that and we’ll give him an opportunity to show us what he can do.”

Pelfrey will be examined on Monday by Dr. James Andrews, at which time a final decision will be reached on his status. On Thursday, the right-hander said he was “99 percent” certain he will undergo season-ending Tommy John surgery on his elbow.

At the very least, the Mets hope Schwinden can be a stopgap until Chris Young is deemed ready for a major league return. The veteran righty, who underwent surgery last May to repair a torn anterior capsule in his shoulder, is scheduled to throw 70 pitches in a simulated game on Monday and could make a minor league start later in the week.